/*************************************************************************
 * File Name:    Same_Tree.cc
 * Author:       zero91
 * Mail:         jianzhang9102@gmail.com
 * Created Time: 2013/11/13 22:14:27
 * 
 * Description:  
 |------------------------------------------------------------------------
 | Problem: Same Tree
 |
 | Given two binary trees, write a function to check if they are equal or not.
 |
 | Two binary trees are considered equal if they are structurally identical
 | and the nodes have the same value.
 |------------------------------------------------------------------------
 ************************************************************************/

#include <iostream>
#include <fstream>
#include <sstream>
#include <algorithm>
#include <vector>
#include <queue>
#include <stack>
#include <deque>
#include <map>
#include <set>
#include <functional>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cctype>
#include <cmath>

using namespace std;

/**
 * Definition for binary tree
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */
class Solution {
public:
    bool isSameTree(TreeNode *p, TreeNode *q)
    {
        if (p == NULL && q == NULL) return true;
        if (p == NULL || q == NULL) return false;
        if (p->val != q->val) return false;
        
        if (!isSameTree(p->left, q->left)) return false;
        return isSameTree(p->right, q->right);
    }
};

